Figure 4. Current trace in the activation of TRPC4β by Gα_i2. (A) Representative current traces recorded at -60 mV. The time course of activation of TRPC4β by Gα_i2 was delayed in the presence of 10 mM EGTA in the patch pipette, in contrast to the current recorded with the low-calcium buffered internal solution (0.5 mM EGTA). (B) The current-voltage (I-V) relationship of TRPC4 showed a typical doubly rectifying shape. The I-V relationship shown in a and b was obtained at point a and b of (A).